Dizziness or lightheadedness may occur as your body adjusts to the medication. Headache or flushing may also occur. If any of these effects persists or worsens, tell your doctor or pharmacist promptly.
Tell your doctor right away if you have any serious side effects, including: swelling hands/ankles/feet, fainting, fast heartbeat, signs of kidney problems (such as change in the amount of urine), symptoms of a high potassium blood level (such as muscle weakness, slow/irregular heartbeat), severe/persistent diarrhea.
Some people who already have severe heart disease may rarely develop worsening chest pain or a heart attack after starting this medication or increasing the dose. Get medical help right away if you experience: worsening chest pain, symptoms of a heart attack (such as chest/jaw/left arm pain, shortness of breath, unusual sweating).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.